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Species · Alaska · BBS 2025 Release · 1966–2024

Surf Scoter Population Trend in Alaska

All statesWaterfowl

Surf Scoter in Alaska has fallen sharply: down 61% on the route-weighted index since 1986.

-61%Since 1986TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
24Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
30YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Surf Scoter Trends in AlaskaNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

long arc declinecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Surf Scoter has fallen sharply in Alaska: down 61% on the route-weighted index since 1986.

Surf Scoter Population Forecast in Alaska

If the recent trend holds, Surf Scoter in Alaska is projected to fall about 93% by 2029 — from 1.2 in 2024 to a central estimate of 0.09 (95% range 0.00–2.3). A 5-year backtest shows a typical error of ±275.8%, with 100% of held-out values landing inside the 95% band.

-93%Change by 2029TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
0.09Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–2.395% range95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
±275.8%Backtest errorBacktest errorTypical error when we hold out the most recent years, forecast them, and compare to what actually happened. Lower means a more trustworthy projection.Full methodology →
If the recent trend holds, Surf Scoter in Alaska is projected to fall about 93% by 2029 — from 1.2 in 2024 to a central estimate of 0.09 (95% range 0.00–2.3). A 5-year backtest shows a typical error of ±275.8%, with 100% of held-out values landing inside the 95% band.19842029
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →95% low95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →95% high95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
20250.190.002.4
20260.170.002.4
20270.140.002.4
20280.110.002.4
20290.090.002.3

Surf Scoter Survey Routes in Alaska

Routes recording Surf Scoter in Alaska.
Recent countThe raw number of individuals recorded on this route in its most recent survey year. A single-route tally, not a trend.Full methodology →
Juneau5120232003
Haines4920241989
Juneau Alt3419861985
Sitka (Short)3219921984
Zimovia Strt2020241995
Sitka1619971994
Petersburg1219871987
Mitkof Isle1119981996
Zarembo1020122012
Yakutat1020241994
Skagway919941994
Monahan619991999
Kotzebue (Short)519861986
Birch Lake420232023
Maclaren420141991
Kobuk River (Short)219911991
Lake Louise220032003
Galbraith L.120172017
Ketchikan120171996
Dillingham119931993
Red Dog120242022
Petersville119921992
Kanuti Lake120182018
Kugarak (Short)119871987

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.